Underhill State Park is within the 39,837-acre Mt. Mansfield State Forest, on the headwaters of the Browns River at about 2,000 feet elevation. It lies on the west slope of 4,300-foot Mt. Mansfield, the state's highest peak, just across the summit ridge from the Stowe ski area. The high elevation and harsh climate support unusual vegetation. Season runs from the Friday of Memorial Day weekend through the second Monday in October.